What are the degrees of freedom in an independent t-test when 40 people are in each of the treatment and control groups?
A) 39
B) 40
C) 78
D) 80

Question

Quizplus · Accepted Answer

The degrees of freedom in an independent t-test with equal sample sizes can be calculated using the formula df = n1 + n2 - 2, where n1 and n2 are the sample sizes of the treatment and control groups, respectively. Substituting in the values given, we get df = 40 + 40 - 2 = 78. Therefore, the correct answer is choice C.

What Are the Degrees of Freedom in an Independent T-Test